Download THE MUSCULAR SYSTEM (Section 2)

THE MUSCULAR SYSTEM
(Section 2)
WARM-UP
Complete
the BONES QUIZ
BONUS QUESTION! (WORTH ONE POINT)
NAME ONE TYPE OF MOVABLE JOINT
MUSCLES
A
MUSCLE IS AN
ORGAN THAT CAN RELAX AND CONTRACT
 PROVIDES THE FORCE TO MOVE YOUR BODY
PARTS
 VOLUNTARY
MUSCLES: Muscles that you are able
to control
 INVOLUNTARY MUSCLES: Muscles that you cannot
control
3 TYPES OF MUSCLES

1.
SKELETAL MUSCLES
 Move
 The
bones
most common type of muscle
 TENDONS
are thick bands of tissue
that attach muscle to bones.
 Voluntary
 Contract
 Look
muscles
quickly and tire more easily
striped, or Striated (STRI ay tud)
 2.
CARDIAC MUSCLE
 Found
 Is
only in the HEART
striated, like the
Skeletal Muscles

3. SMOOTH MUSCLES
 Found
in:
 Intestines
 Bladder
 Blood
vessels
 Other
internal organs
 Involuntary
 They
muscles
work without you thinking about it
 Non-striated
 Contract
muscles (not striped)
and relax slowly
STRIATED MUSCLE (Skeletal and Cardiac)
NON STRIATED MUSCLE (Smooth)
Other key points to know:

SKELETAL MUSCLES work together to make you move

When one muscle of a pair CONTRACTS, the
other RELAXES

Muscles always pull

Muscles become larger or smaller over time


Depends on whether or not they are used!

Used muscles= BIGGER

Unused muscles= SMALLER
Blood carries energy-rich molecules to the muscle

Lets them do their work
In summary…

Muscles help you move!

They attach to bones with TENDONS

Involuntary vs. Voluntary Muscles

Striated vs. Non-striated

Three types:
 Skeletal
 Cardiac
 Smooth
FUN FACTS!
We have more than 630
muscles in our body.
More than 30 of our
muscles are in our
face – that’s how
we can make
different
expressions (happy,
sad), talk and move
our eyes around!
Scientists estimate that our eye muscles
move more than 100,000 times a day!
STREET GYMNAST
WHAT MUSCLES LOOK LIKE
Your muscles need Glycogen (muscle sugar) in order to
function. When the glycogen is broken down into energy for
the muscles a waste product called lactic acid is produced. A
buildup of lactic acid decreases the muscles’ ability to
contract and Muscle Fatigue sets in.
DO THIS:
Hold a book in each hand. Raise one arm straight out
parallel to the ground and the other arm down at your side.
Compare the feeling in each arm...
**keep track of how long you can hold the books for and
which arm gets tired faster!
How long did you hold the book before fatigue got the
better of you?
________ minutes ________ seconds
Which arm felt the fatigue the most?
The straight arm or the arm by your side?
Which muscles experienced the most fatigue?
Biceps
triceps
deltoids
pectoralis major